This PR adds intersection operation on `DHashMap`/`HashMap`/`HashSet`
and provides several lemmas about its behaviour.
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Co-authored-by: Markus Himmel <markus@himmel-villmar.de>
This PR adds adds union operation on `DHashMap`/`HashMap`/`HashSet` and
their raw variants and provides lemmas about union operations.
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Co-authored-by: Paul-Lez <paul.lezeau@gmail.com>
Co-authored-by: Markus Himmel <markus@lean-fro.org>
Co-authored-by: Markus Himmel <markus@himmel-villmar.de>
(Almost) only typos in constant names and doc-strings were considered;
grammar was not considered. Also, along others,
`mkDefinitionValInferrringUnsafe` has been fixed :-)
### Preliminary PRs:
- [x] #4597
- [x] #4599
- [x] #4600
- [x] #4602
- [x] #4603
- [x] #4604
- [x] #4605
- [x] #4607
- [x] #4627
- [x] #4629
### Quick overview over API/naming changes compared to `Lean.HashMap`
and `Batteries.HashMap`:
#### Lean
* `find?` -> `get?`/`getElem?`
* `find!` -> `get!`/`gtetElem!`
* `findD` -> `getD`
* `findEntry?` -> not implemented for now
* `insert'` -> `containsThenInsert` (order reversed in result)
* `insertIfNew` -> `getThenInsertIfNew?` (order reversed in result)
* `numBuckets` -> `Internal.numBuckets`
* `ofListWith` -> not implemented for now
* `Array.groupByKey` -> not implemented for now
* `merge` -> not implemented for now, but you can use `insertMany`
#### Batteries
* `modify` -> not implemented for now
* `mergeWith` -> not implemented for now
* `mergeWithM` -> not implemented for now
